New robot can operate on eyes with more accuracy than a human surgeon

Date: 10 November 2016 11:34

"Axsis, a system developed by the UK-based Cambridge Consultants, is a small, teleoperated robot with two arms tipped with tiny pincers. It’s designed to operate on the eye with greater accuracy than a human.

Cataract surgery requires a steady hand, and the most common complication arises when a surgeon accidentally pierces the back of the lens, a thin membrane that is only a few millimetres off target, causing hazy vision.

Axsis aims to prevent this kind of human error. The device’s articulating pincers are mounted on arms about the size of drinks cans, with extremely light, strong “tendons” made of the same material NASA uses for its solar sails. These pincers can sweep across a 10-millimetre space – the size of the lens of the eye. This is just a demonstrations model; in the final product, the pincers will be replaced with scalpels.

To control the robot, the surgeon sits at a station nearby and uses two 3D haptic joysticks to move the pincers while watching their work on a screen. The image on the screen is enlarged, so the surgeon can make more precise movements, with the pincers operating at a tiny scale not possible with the human hand.

One benefit of the system is that the software disables certain boundaries from being breached. “It won’t let you make the mistake of punching through the back of the lens,” says Chris Wagner, the lead roboticist on the project.

Ian Murdoch, an ophthalmologist at University College London, says he is interested in the idea that Axsis prevents piercing the back of the lens. “This happens in about 0.1 to 0.7 per cent of cases,” he says. “If the complication rate is less then this would obviously be great.”

However, Murdoch wonders if Axsis really offers much advantage over existing advanced cataract surgery techniques, such as laser cataract surgery.

Axsis’s creators say that cataract surgery is just the start. “I think it will quickly find more applications,” says Wagner. It could, for example, be used in gastrointestinal operations. Put the pincer end of Axsis on an endoscope and it could solve any small problems – like removing polyps – then and there. “Nowadays, when you find something in the colon or in the stomach, you leave it there,” says Wagner.

Wagner hopes the robot could one day enable operations surgeons can only dream of. “We just want to push forward what’s possible.”"